1. Field of the Invention
This invention in general relates to breathing apparatus, and particularly to underwater breathing apparatus incorporating flexible breathing bags.
2. Description of the Prior Art
In undersea work, it is absolutely required to conserve, through good design, as much as possible of the diver's total expendible energy so that it may be fully applied toward a specific task. The diver should not have to exert much-needed energy in fighting his equipment and his environment. For example in underwater breathing apparatus incorporating breathing bags, when the diver is in the swimming position the buoyancy of the breathing bags acting at one point in conjunction with the weight of certain components acting at another point tends to produce a restoring moment which the diver must fight. Large inspiratory or expiratory efforts must be avoided, and in general the diving rig must be comfortable to avoid an adverse reaction by the diver.
The components of many diving rigs are mounted on a flat plane of metal or other rigid material and occasionally covered with a shaped cover. The resulting package is esthetically pleasing however the diver's back is not a flat plane and in use at hundreds of feet in the water, esthetics become of little significance to the diver in view of the discomfort and instability experienced. Breathing bags have been incorporated in such structures and have been positioned high on the diver's back at the top of the inside of the package, in conjunction with an exhaust valve which determines the pressure of the breathing gas in the system. This placement of components results in a system which is quite diver position sensitive so that the pressure varies excessively, to the discomfort of the diver.
Another approach has been to contour the component holder to the normal curvature of a man's back. The problem arises however that the normal curvature for one person is an abnormal curvature for another person so that variation in human sizes and build limits the usefulness to other than one person for whom the rig was designed.
It is therefore a primary object of the present invention to provide underwater breathing apparatus that substantially reduces, and in some cases eliminates, the inadequacies of prior art devices.